Knockdown scaffolding



Aug. 7, 1934.

H. J. MARLOWE 1,969,656

KNOCKDOWN S CAFFOLDING Filed Nov. 3, 1931 3 Sheefis-Sheet l INVENTOR Harah'J/Var/azbe A BY ATTORNEYS ,1934. H. J. MARLOWE 1,969,656

KNOCKDOWN SCAFFOLDING Filed NOV. 5, 1951 3 Sheets-Sheet 2 lNVENTOR ATTORNEYS Aug. 7, 1934.

H. J. MARLOWE 1,969,656 KNOCKDOWN SCAFFOLDING Filed Nov. 5, 1931 I Til- TAU.

ATTORNEYS 3Sheets-Sheet s A Patented Aug. 7, 1934 UNITED STATES PATENT OFFICE I 1,969,656 KNOCKDOWN SCAFFOLDING Harold J. Marlowe,

Brooklyn, N.

Y-, assignor,

by mesne assignments, to Marlowe Devices,

Inc.,

a corporation of Delaware My present invention relates to scaffolding in the generic sense of the term, that is to say, while the invention is especially adapted for embodiment in a scaffolding such as that commonly employed in building work, many features of the invention are suitable for use wherever a knockdown or collapsible support structure of any character is desired.

An object of the invention is to provide a scaffolding or a scaffold frame of extremely simple, practical construction, capable of being carried to the site of use in knock-down or collapsed condition and then readily set up (by one man if desired) without requiring the use of any special tools or any skilled workmen.

Another object is to provide a knock-down scaffolding, the constituent parts of which may be conveniently manufactured from ordinary steel bar or rod stock, typically angle irons and T irons and pipe stock and angle brackets and in which the various parts are readily interchangeable one with the other so that the erection of a scaffolding is facilitated due to the fact that no special care need be exercised in assembling the constituent parts thereof.

Another object of the invention is to provide a scaffolding which may be built up to any desired height and in which the individual scaffolding sections are rigid and the superimposed sections are rigid one with the other.

Another object is to provide a scaffolding consisting of a plurality of knock-down scaffolding sections capable of superimposition one upon the other without the need of securing devices to connect the sections and in such a manner that all sections are firmly supported.

Another object of the invention is to provide a scaffolding structure in which a number of substantially identical knock-down scaffold frames or sections may be united both laterally and vertically to the end that both the width and the height of the frame work may be indefinitely increased and the completed structure effectively tied together.

Another object is to provide apparatus of this character in which there is no danger of bending or breaking or warping or otherwise injuring the constituent parts of the structure during the process of transportation assembly or disassembly.

Another object of the invention is to provide a scaffolding structure in which the strains and stresses are taken directly by substantial metal bars in contra-distinction to utilizing bolts or rivets or equivalent securing devices and subjecting them. to severe shearing stresses.

In accordance with one embodiment of the invention, the scaffolding includes a series of comer uprights connected by horizontally disposed, longitudinal and transverse bracing and platform receiving bars which mechanically in- 6 terlock with the end posts and are secured against slippage or inadvertent displacement. The standards as well as the horizontal elements are preferably formed of standard bar, rod or tube stock to afford maximum rigidity in a relatively light frame. The horizontal scaffolding sections may support planks or other platform elements disposed either. horizontally or transversely of the scaffolding sections. Laterally adjacent scaffolding sections may be tied together by hori- I0 zontal tie structures similar in construction to the horizontal frame forming members and having a similar mode of attachment to the uprights of adjacent scaffolding sections.

Means is provided for permitting the superimposition of one scaffolding section on the other without the use of special securing devices. With this end in view spaced angle brackets are secured to the ends of the uprights of one section and project therebeyond so that they may receive between them the unbracketed angular end upright of a subjacent or superjacent frame as the case may be.

In some instances instead of making the scaffolding as a knock-down structure, the end sections or the side sections or both may be formed as collapsible structures. In this case I preferably utilize collapsible cross bars hinged together and hinged to the legs which they connect. These bars are provided with a special butt joint arrangement designed to transmit substantially all of the load against the uprights and against the abutting ends of the sections rather than imposing shearing stresses on the rivets or other pivot devices about which the collapsible scaffolding members swing.

The invention may be more fully-understood from the following description in connection with the accompanying drawings wherein:-

Fig. 1 is a fragmentary perspective view illustrating one complete scaflolding section connected to a laterally adjacent section,

Fig. 2 is an enlarged elevational detail showing the connection of a cross bar to an upright,

Fig. 3 is a sectional detail on the line 33 of 10 Fig. 2,

Fig. 4 is a disassembled perspective view showing the manner in which one scaffolding section may be superimposed over the other without the use of securing devices,

Z Li

through the openings Fig. 5 is an end view of an alternative form of construction in which the end frames of the scaffolding are of the collapsible instead of the knock-down type. In this view the dotted lines indicate the scaffolding in partially folded condition,

Fig. 6 is an enlarged perspective fragmentary broken view showing one of the folding cross bars in partially folded condition and indicating the details of the cross bar construction,

Fig. 'I is a perspective view similar to Fig. 1 but illustrating a further modification,

Fig. 8 is an enlarged sectional line 8-8 of Fig. '1,

Fig. 9 is a perspective view of a foot piece, and

Fig. 10 is an enlarged perspective view of the lower end of one of the uprights.

Referring flrst to Figs. 1 to 4 of the drawings, I have illustrated a skeleton frame or scaffolding consisting of four corner posts 10 of identical construction, each of these posts being formed of ordinary angle iron stock with its V recess facing inwardly. Each flange of the angle iron standards is provided with T-shaped openings 11 therein adapted to receive the reduced ends 12 of the longitudinally and transversely extending, standard-connecting bars 13 and 14. These bars are of ordinary T-shape in cross section to afford flat, platform-receiving upper surfaces and their reduced ends define shoulders 15 adapted to abut the inner face of the standard flanges when the bars are in place.

In assembling the bars with respect to the standards, the reduced bar ends 12 are passed 11 in the standard. Suitable plates 16 having openings therein corresponding to the cross section of the reduced ends 12 slip over these ends against the outer faces of the standards and a cotter pin or equivalent securing device 17 is then passed through a prepared opening 18 in the bar ends 12 to prevent inadvertent withdrawal of the bars from their interlocking and abutting engagement with the standards.

In order to avoid interference between the connections of the transverse and longitudinal bars of the standards, each set of transverse bars is spaced slightly above or below the corresponding set of longitudinal bars.

Planks 19 which are laid on the skeleton frame structure to define the scaffolding platform, may extend either transversely or longitudinally of the scaffolding. The arrangement is such that with the planks in any position spanning two horizontal rails of the scaffolding, one longitudinai rail and at least two transverse rails will serve as guard rails to prevent the workmen from tumbling off the platform.

When a plurality of laterally adjacent sections of scaffolding such for instance as the sections A and B shown in Fig. 1, are to be connected together, the adjacent standards of the two sections are lined up and connected by relatively short horizontal tie members 23. These members also comprise steel or iron bars of T-shape in cross section having reduced ends which are connected to the adjacent scaiioiding sections in the same manner as the reduced ends of the lower frame bars 13 and 14.

In order to permit the convenient and facile superimposition of one scaffolding section upon another, the top of the standards 10 may have angle brackets 20 and 21 secured respectively, to their inner and outer surfaces and extending above the top of the standards to define V-shaped detail on the 1,9eaese pockets 22 for receiving the feet of the similar standards of a superiacent section.

with the four feet of a superimposed section received in the pockets deflned by the angle brackets of a lower section, it will be apparent that the upper section is restrained against lateral movement in any direction and the weight thereof sustained directly upon the posts of the lower section.

In Figs. 5 and 6 I have illustrated another embodiment of the invention in which standards 30 corresponding to the standards 10 are utilized and these standards may be connected by longitudinally extending bars (not shown), the ends of which appear at 31 corresponding to the bars 13 of Fig. 1 and similarly connected to the standards 30. In this instance, however, the transverse horizontal bar portions designated generally at 32 are of folding construction consisting of two sections 33 and 34, permanently pivotaily connected as at 35 to the respective standards.

The inner ends of the sections 33 and 34 are pivotaily connected together as at 36. Here the sections of the cross bars 32 are of angle iron construction and the upper flange. 3'! of the section 34 is adapted to overlap the unflanged end 38 of the section 33 in order to provide a butt or rule joint which prevents the pivot 36 from moving in a downward direction and permits collapse of the sections only upon movement of their pivotally connected ends in an upward direction.

By the present invention, substantially all of the shearing stress is taken off the rivet 36 and the pivot members 35 and 36, and the standards 30 and the cross bar sections 33 and 34 are caused directly to take the stresses.

With this end in view the end of the section 33 is provided with an abutment face 39 adapted to engage the flange 30a of standard 30 when the section 33 has been swung to horizontal position. A similar abutment surface 40 is associated with the section 34 and is engageable with the flange 30b of this associated standard 30. In like manner the inner end face of the vertical flange of the angle bar 34 is provided with an abutment surface 41 to engage with the corresponding surface 42 of the vertical flange of the angle sect-ion 33. Member 38 may be in the form of a straight bar welded against the inner face of the vertical flange of the angle 33.

In operation when the scaffolding is moved from the collapsed dotted line position of Fig. 5 into the full line extended position, the straightening out of the cross bars 32 will be accompanied by abutment of the flanges 39 and 40 against the flanges 30a and 30b and by the abutment of the flanges 4i and 42 against each other, whereby the stresses are taken substantially entirely by the steel framework itself instead of by the rivets 35 and 36 which pivotaily connect the cross bar sections 33 and 34 to each other and to the frame work.

If desired not only the end frames. that is to say, the standards and the transverse bars may be made of collapsible construction, but the longitudinally extending bars may be similarly constructed whereby the entire frame work could be folded into a compact space.

Many skeleton frameworks for various purposes might be built up of the same knock-down or collapsible construction as that disclosed herein and I therefore intend, except where otherwise specifically noted, that the term scaffolding will be interpreted in its broadest sense to include all skeleton frameworks upon which temporary or permanent platforms or equivalent devices may be mounted.

In Figs. 7 to 10 of the drawings I have illustrated an alternative form of the invention which utilizes the folding end bars of Figs. 5 and 6 but in which the application of the longitudinally extending side bars is rendered extremely simple, so simple in fact that a single workman may unaided erect the scaffolding framework. In accordance with this form of the invention I eliminate cotter pins or other securing devices for holding the ends of the frame bars in interlocking relationship with the standards and utilize a construction in which the frame bars interlock by gravity as they are assembled with respect to the standards.

In this instance the longitudinally extending frame bars 45 are of tube stock and short rods 46 are driven into the ends of the tubes 45. These rods at their outer ends have heads 47 preferably of a diameter equalling the outside diameter of the tubes 45. By the use of a gauge member (not shown) the short rods 46 are drive fitted into the pipe ends so that the heads 47 are spaced from the ends of the pipe to a distance approximately equal to the thickness of the angle iron stock used in the corner uprights 48.

Such spacing affords in the unitary frame bar thus formed, a reduced neck portion 49 between the end of the pipe 45 and the head 47 of the rod 46. A frame member thus formed may be assembled in interlocking relationship with the corner uprights in very simple fashion typically by the formation of key hole slots 50 in the standards. The larger ends of these slots are of sufficient diameter to permit the heads 4'7 to be inserted through them and the lower reduced ends of the slots are of sufiicient width to snugly accommodate the neck portion 49 of the frame bar. Thus one of the frame bars 45 may be mechanically connected to a corner upright by simply inserting the head 47 through the key hole slot and permitting the frame bar to drop by gravity to position where the neck 49 rests in the lower end of the slot.

As suggested above the horizontal frame bars are so designed that there will be very slight room for play between these bars and the corner uprights. In order to take all play 'out of the structure however I may employ pairs of pull bars 51 anchored near the tops and bottoms of the uprights and having their other ends connected to a ring 52 which is in turn attached to an eye bolt 53 forming part of a turn buckle 54.

For practical purposes I have found that if the two front parts, that is the two parts away from the side of the building, are provided with the necessary pull rods 51, the frame may be effectively tightened without using a corresponding turn buckle or corresponding set of pull rods with the corner uprights which are adjacent the wall of the building.

The reason for this is as follows:-When the turn buckle 54 is tightened and tends to draw the front uprights together, these uprights will act in a fashion as pivot members, pivoting on the horizontal members and the rear uprights will either be drawn together by the pull on the front uprights or moved apart by such pull depending upon whether the bars 51 are connected to the outer edge of the front upright members 48 or to the inner edge thereof. In either event the rear frame bars 45 become firmly tightened against the rear parts and the desired rigidity is obtained.

It will be obvious that instead of using the folding end bars, all of the horizontal members of the frame structure of Fig. 7 might be similar to the bars 45. The angle iron uprights may be provided with any desired number of key hole slots 50 therein in order to permit the bars 45 to be attached at any desired elevation. Similarly the uprights may have any number of openings therein within which to anchor the pull rods 51.

In this form of the invention I have shown inner and outer angle iron brackets 55 and 56 connected to the lower ends of the uprights 48 and projecting below them to provide a V-shaped pocket 5'7. When superimposing one frame upon another the pocket 57 will be slipped over the upper end of the upright to a subjacent frame structure and I preferably associate units such as that shown in Fig. 9 for coaction with the pocket forming brackets of the uprights of the lowermost frame unit. These feet may comprise castings including a relatively spacious floor base portion 58 from which rises an angular member 59 of V-shape in horizontal cross section and adapted to enter the pocket 57 of an associated upright. I

It will thus be seen that there is herein described apparatus in which the several features of this invention are embodied, and which apparatus in its action attains the various objects of the invention and is well suited to meet the requirements of practical use.

As many changes could be made in the above construction, and many apparently widely different embodiments of this invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A knock down scaffold including corner upright members joined together by horizontally extending bars adapted to support planking and forming with the upright members a substantially rectangular scaffolding section, the horizontally extending supporting bars on at least two opposite sides of the section being connected to the upright members by detachable connections formed by the reduced ends of the bars extending into slots in the members, the bars on at least one of said sides being connected to the upright members intermediate the lateral edges thereof, and adjustable tensioning means connected to corresponding lateral edges of the uprights at said side of the scaffold to brace said side, the bracing effect being transmitted to the other side of said scaffold through the horizontally extending bars joining said sides.

2. A knock down scaffold including two pairs of corner upright members, the members of each pair being connected together by collapsible members which when extended rigidly join the upright members of a pair together, horizontally disposed supporting rods detachably connected at their ends with opposed uprights of different pairs to form a substantially rectangular scaffolding section, said supporting rods being connected to the uprights intermediate the lateral edges thereof, and adjustable tensioning means connected to corresponding lateral edges of opposed uprights at one side of the scaffold section to brace said side, said bracing effect being transmitted to the other bracing eiiect being transmitted to the other side of said scaiioid through the rigid connections between the upright members of a pair.

HAROLD J. MARLOWE. 

